Television continues to spread.

• Author: Roodman, David Malin
• Position: Impact of television on viewers

In 1946, only 8,000 homes had television. But the number reached 180,000 by 1948, 4 million by 1950, and 41 million by 1955. Since then it has risen an average of 8 percent annually. In 1994, some 886 million households had TV - an audience that amounted to about half the world's people (ILLUSTRATION FOR GRAPH OMITTED).

TV took root earliest among World War II victors. The United States had more than 90 percent of the world's televisions in 1951. Most of the rest were in the United Kingdom. Today, in these and other industrial countries, 97 percent or more of all homes have at least one set. Since the seventies, the television explosion has moved to countries that are poorer but rapidly adopting western-style consumerism. Between 1975 and 1994, the number of households with TVs jumped 360 percent in Latin America and 950 percent in Asia. Since the developing world has a rapidly growing population and relatively fewer homes with TVs, growth there could continue for years, pushing the global total toward 2 billion.

As these trends suggest, the count of households with television corresponds closely with the shifts toward resource-intensive ways of life. But television is not only an indicator of change; it is an agent. With the possible exceptions of the telephone and the automobile, no other technology has so revolutionized how people live, and how they see the world.

Television can entertain, but it can also educate. For example, in the remote Peruvian Andes, one priest has used video tapes to teach villagers about sanitary habits and the treatment of diarrhea, a childhood killer. In some countries, images of freedom beamed in from outside have worked to undermine dictatorships.

Yet, one of the clearest impacts has been on how people spend their time. Citizens in every European country watch at least 2 hours a day on average, with the British topping the list at 3.5 hours. Americans surpass...